dickson



(No Model.)

. A. A. DIGKS ON METHOD OF REDUGING METALLIC SAND 0R PULVERIZED ORES.

No. 569,820. Patented Oct. 20, 1896.

PATENT FFICE.

AROIIIBALD A. DICKSON, OF TORONTO, CANADA.

METHOD OF REDUCING METALLIC SAND OR PULVERlZED ORES.

SPECIFICATION forming part of Letters Patent No. 569,820, dated October 20, 1896.

Application filed April 13,1895. dais-1N0. 545,631. (No specimens.) Patented in Canada September 3, 1895, No. 49,835

To all whom, it may concern:

Be it known that I, ARCHIBALD ANDERSON DICKSON, a subject of the Queen of Great Britain, and a resident of the city of Toronto, in the county of York and Province of Ontario, Canada, have invented. a certain new and useful Improvement in theReduction of Metallic Sands or Pulverized Ores, (for which I have obtained Canadian Patent No. 49,835, dated September 3, 1895;) and I do hereby declare that the following is a full, clear, and exact description of the same.

This invention relates to the treatment of 7' sands (found in large natural deposits) containing iron, copper, gold, silver, and other metals, whereby the same may be readily and economically reduced or smelted.

The improvement is also applicable to equal advantage for use with pulverized, granulated, or finely-divided ores.

Figure 1 of the accompanying drawings shows a suitable breaking-up device for reducing the dried peat to the desired state, a conveyer ,1, a hopper 2, a pair of rolls 3, and a picker at being shown, the operation of which is apparent. Fig. 2 is a vertical section of the pressing apparatus.

In carrying out my process I use peat as a combustible binding material for the sand or granulated ore, as this material is known to possess many advantages over other materials, such as charcoal, coke, limestone, cinders, 830., heretofore employed in conjunction with comminu ted ores for smelting purposes.

The employment of peat in metallurgic operations has been in the shape of fuel by itself, and in a reducing-furnace it has been charged in layers interstratified with ore. lVhile the peat has generally been thus used in a loose, partly-dried condition, it has sometimes been subjected to a preliminary charring operation and then used in alternate layers with the broken ore, and it has also been suggested in a British patent issued in 1872 to first out the peat roughly from the bog and, while wet, to pass it through rollers running at different speeds to crush, mix, and deliver it in a thin stream to a peculiar drying apparatus, from which it is taken while hot and only partially free from the damp vapors and further rolled or crushed to rough powder, with which. the ore previously crushed into small pieces is mixed at that stage, and the whole pressed into blocks ready for charging into the smelting-furnace. In that process it was definitely proposed to utilize the hot gases from the drying or carbonizing of the peat, thus necessarily inferring that a large proportion of the volatile elements had been liberated, and that the fiber had been broken and the W1] ole pressing operation performed While the material was in a heated condition.

It is essential in the smelting of metallic sands and fine1ydivided ores that the fuel used shall possess the maximum of combustible qualities and those capable of generating the most intense heat, combined with a capacity for binding the metallic particles together and in conjunction with the fuel elements in such a durable manner that they cannot either be blown out or dissipated by the blast, fall through to the bottom of the cupola before fusing, or be burned up by direct contact with the fire before a suiiicient body of metal has been recovered from the particles to form properly into globules.

My invention, therefore, is directed to this end, and I will now here describe my invention in such detail that those skilled in the art may put the same into practice, and will then point out the novel features in the claim.

It must be borne in mind that the maximum amount of volatile and combustible matter must be retained in the peat, that its fiber must be broken as little as possible in order that it shall form an efficient binding medium, and that it shall have the highest possible density and specific gravity consonant with smallness of bulk and proper dryness to fit it for use in reducing or smelting metallic sands and pulverized ores. I propose to combine peat possessing all those necessary qualities with the metal-bearin g materials in the form of evenly pressed blocks possessing great density and hardness, and capable of sustaining their integral form under the fiercest heat, and remaining incandescent and practically intact until the constituent metals have become melted and properly fused.

It is necessary that the peat shall be first dried to about the degree of humidity in the atmosphere, and then crushed between rolls or like devices which will reduce it to the re- TOO quired fineness without destroying the fiber or liberating the constituent gases. In this condition I mix the peat with the metallic sand or pulverized ore, as the case may be, in such proportions as may be deemed desirable and stir them together in a suitable mixer, being careful to see that the materials are thoroughly and evenly incorporated. (I have found good results from a mixture of peat and ore in equal proportions by weight, but this may be varied according to different conditions.) It is essential that the peat and ore shall be absolutely cold at this stage, and that the compression of the combined materials into blocks shall take place without the application of any artificial heat whatever. The preferred pressing apparatus is that used by me for forming blocks of peat-fuel, as I have found such an arrangement highly suitable for the purpose of my present invention. This pressing apparatus is shown in Fig. 2 of the diagram, which represents a vertical sectional elevation and consists of vertically-arranged forming tubes or cylinders a (of the diameter to be given to the blocks) open at both ends with plungers 19 operating therein to pack and compress the mixed materials by successive strokes (one stroke for each block formed) as it is fed into the inlet ends of the forming-tubes. This feed may be from a common hopper, as shown, or each tube may be supplied separately, if desired. Each of the forming-tubes will be furnished with a closely-fitting but yielding resistance-block c, which will prevent the first charge of loose peat and ore from immediately discharging at the outlet end and afford a base upon which the first block can be formed. \Vhen the plunger 1) has retired, afresh charge of combined material will be ready at the inlet end of the forming-tube to be forced in at the return stroke, and to form the second block upon the base offered by the first block the internal resistance-block first mentioned having been forced forward. Each succeeding charge of material forms a block of itself in contact with but separate from the preceding block, and when a sufficient number have been formed the first resistance block will be automatically ejected from the forming-tube, and the operation proceeds, forming one block upon the other so long as the feed of material continues, the blocks being successively ejected from the tubes, as will be readily understood.

d d represent the formed blocks, and I have shown three sets of pressing devices to illustrate diflereut stages of the operation.

By using vertical molding-tubes the gravity of the mixed peat and ore aids in furnishing charges of material, each of even density from top to bottom and side to side, and this arrangement also helps to reduce undue friction and assist in the easy delivery of the finished blocks.

Proper means being of course provided for the egress of the air from the matenial and from the tubes, the effect of the above operation is to firmly consolidate the fibrous, carbonaceous, and gaseous matters of the peat and the'fine particles of sand or ore incorporated therewith into hard compact blocks of somewhat the appearance of coal, and the friction to which they are subjected while passing through the forming-tubes results, by the fracture or compression of the minute cells contained in the fibers at the surfaces of the blocks, in the liberation of just sufficient of the indigenous tarry matter of the peat to impart a glaze or coating to the blocks of an atmospheric and Water resisting material.

It will be seen that the peat fibers in the body of the blocks are left intact and unbroken, and there being no artificial heat applied there is no danger to be feared from the formation of gases during the pressing operation. All volatile matters are retained in the peat, and the blocks of peat and ore manufactured by my process are very dense and compact. Although these blocks may be of uneven length, (which is not undesirable) according to differences of density in individual lots of peat, the full stroke of the plunger is given to each charge, and the yielding resistance being always the same, a uniform pressure is given to all of the blocks and their consistency and density will invariably be the same throughout, thereby insuring an even and steady combustion in the reducing-furnace and giving a certainty that the metal will melt and fuse or form into globules before the fuel elements have become exhausted or the block breaks down.

I do not think it necessary to further describe the process of smelting, as from this point there need be no change from the wellknown procedure in recovering iron or other metals.

Although I have been particular to describe devices and operations eminently suitable and convenient for the effectual carrying out of my process, it must be understood that these may be varied or modified according to judgment without departing from the principle or sacrificing the advantages of my invention.

What I claim, and desire to secure by Letters Patent, is

The improved art or method of reducing metallic sands, or pulverized ores, in connection and combination with peat as a binding and combustible material, which consists, essentially, in the following sequence of operations, viz: first, drying the peat sufficiently to deprive it of all but the atmospheric degree of moisture; second, breaking or separating it into fragments which retain the natural fiber practically unbroken; third, incorporatin g or mixing such peat with the metallic sand or pulverized ores while both materials are perfectly cold; fourth, causing such combined materials to fall by gravitation into a forming tube or mold in evenly-disposed successive the constituent metals are fused and run ofif, 10

substantially as set forth.

In testimony whereof I have signed in the presence of the two subscribing witnesses.

ARCHIBALD A. DIOKSON.

W'itnesses:

JAMES R. SILLIMAN, ARTHUR G. JOHNSTON. 

